Despite its power, the tool is for most users:

Flashing a modem is an advanced procedure that generally follows these steps: huawei h155-381 unlock code required #167743 - GitHub

Follow the on-screen instructions to select the .app file and start the flashing process.

Tool — Huawei Modem Flash

Despite its power, the tool is for most users:

Flashing a modem is an advanced procedure that generally follows these steps: huawei h155-381 unlock code required #167743 - GitHub

Follow the on-screen instructions to select the .app file and start the flashing process.